Improvement in pastes for making stereotype-molds



S. CBU M P.

Paste for Making Stereo type Molds.

Olly. 1.

No. 134,196. Patented Dec.24, 1872.

Jig. 3.

mum: gamma All. PHDTU-UTHOGRA PHIL CONX/OSBOIPNES P1106555) UNITED STATES PATENT OFFICE.

SAMUEL GRUMP, OF NEW YORK, N. Y.

Specification forming part of Letters Patent No. 134,196, dated December 24, 1872.

To all whom it may concern:

Be it known that I, SAMUEL CRUMP, of the city, county, and State of New York, have invented a new and useful Improvement in Paste for Making Stereotype-Molds, of which the following is a specification: I

My invention consists in mixing asbestus, in large or small proportions, with the paste which is used in making papier-mach stereotypemolds.

The paste is used in pasting together various sheets of paper forming the matrix and backing sheets and also in filling up the cavities in certain parts of the mold between the sheets forming the matrix and the backing sheets.

The properties of my improved paste are:

' A great hardness and solidity when dry; ability to withstand a high temperature, also to withstand great hydrostatic pressure 'and also drying and settingwithout shrinking or cracking; all of which it possesses in a greater measure than any other paste used, and it imparts the same qualities to the mold.

I propose to fill in the cavities in the back of the matrix, which have hitherto been part-., ly filled with pasteboard in order to obtain the requisite stiffness, entirely with this paste, so that, wit-hthe pasting of the sheets together, the paper will be largely saturated with the paste, which, by virtue of the asbestus contained in it, renders the molds, to a certain extent, fire-proof, so that a greater number of casts of the molten metal can be taken from one mold or matrix than can be taken from the ordinary molds.

Figure 1 is a plan view of a matrix construct: ed according to my improvement. Fig. 2 is a section of a partly-formed matrix-also a form in which the matrix is produced; and Fig. 3' is a section of the complete mold or matrix,

showing the filling of the cavities in the back and the backing-sheets of paper pasted on.

I propose to take the ordinary rye-flour paste used in the common way of making these molds, and mix finely-powdered asbestus with it in such proportions as maybefound best to obtain the best eii'ects in stiffening the mold,

.rendering it clear and sharp when dry and hard, also rendering it fire-proof and durable,

as hereinbefore stated, and apply it in the usual way to the paper sheets a, which are pressed or beaten on the form to be stereotyped, for saturating and pasting them together, then fill up the cavities b altogether with it, as shown at 0, instead of 'partly filling them with pasteboard, and then paste on the backing d with it in the ordinary way.

, Having thus described my invention, I claim as new and desire to secure by Letters Patcut-- The use of asbestus in the paste used for making papz'er-mach stereotype-molds, substantially as specified.

SAML. CRUMP.

Witnesses:

J. E. HINDs, R. S. DIOKIE. 

